The present invention relates to a lubrication system, and more particularly, to a lubrication system for a fan drive gear system in gas turbine engines.
In many gas turbine engines, a low pressure spool includes a low pressure turbine connected to and driving a low pressure compressor, and a high pressure spool includes a high pressure turbine connected to and driving a high pressure compressor. In some gas turbine engines, a fan at the front of the engine is connected to the low pressure spool through a fan drive gear system. One or more supply pumps supply lubricating liquid to the fan drive gear system and one or more scavenge pumps typically scavenge the lubricating liquid from the fan drive gear system. If the scavenged lubricating liquid is highly aerated, a small scavenge pump may not be suitable to scavenge the lubricating liquid from the fan drive gear system, thus causing flow to back up and potentially lead to oil leakage, excess heat generation, and low oil quantity alarms. If a larger scavenge pump is used, that can add weight and take additional space, which is undesirable in systems where weight and space are a premium.